Recently, utilization of a solar battery has become of major interest in view of protection of the global environment. This solar battery as a module is exclusively arranged outside and such a solar battery module is generally composed of a solar battery panel comprising a light-transmission panel and a solar battery element, the solar battery element being provided on the surface which is opposed to the light-receiving surface of the light-transmission plate, and a frame for fixing the solar battery panel thereon. As the fixing frame, for example, there has been widely used a frame having four frame bodies capable of fitting in four directions to the peripheral end portion of the solar battery panel. In this case, there is a problem that the frame should be constructed by fitting four frame bodies into each end portion of the solar battery panel and fixing them each other by means of fixing such as screw, etc. and therefore it takes a long time to assemble them.
Although a sealing material is interposed to fix the solar battery panel onto the frame body, scatter in thickness of the sealing material can cause distortion of the outside dimension of the frame and finally whole solar battery module.
On the other hand, as the sealing material, a butyl rubber is used because of its water shielding characteristic (amount of steam transmitted is comparatively small). However, the butyl rubber is sometimes soften by heat, for example, the butyl rubber causes softening flow at high temperature under a load, for example when the packaged solar battery module is transported to tropics and the panel sometimes settles by its own weight. Therefore, two typical methods are used; one is a method of preventing the panel from settling by filling an elastic member into the gap portion between the lower surface of the panel and the frame body in close vicinity to the butyl rubber sealing material (see Japanese Utility Model Kokai Publication No. 3-10560) and the other is a method of using a silicone sealing material in combination with the butyl rubber sealing material to improve the weathering resistance and heat resistance (see Japanese Utility Model Kokai Publication No. 4-130457). However, even in case of the former method of filling the elastic member, the butyl rubber sealing material is still softened and exposed from the frame to deteriorate the appearance, which results in penetration of rainwater. Thus, the battery functions are inhibited. In case of the latter method of using in combination of the silicone material, since the silicone sealing material has the moisture curing property but is in the form of a paste at normal temperature, it takes several hours to several days to cure the sealing material after coating in an assembling state. Therefore, slight vibration in the uncured condition causes shift occurrence between the panel and the frame at the time of their handling and delivering.
Thus, the present inventors have intensively studied to solve the problem of the troublesome assembling of the above frame structure and distortion of the outside dimension as well as problems of quality and production process due to the butyl rubber sealing material in the above improved sealing method. As a result, the present inventors have found that, when using 1) a frame having a projecting plates for supporting the surface opposed to the light-receiving surface of the light-transmission plate, 2) the projecting plates being provided over the periphery of the end portion of the solar battery panel, 3) the frame permitting the light-receiving surface of the light-transmission plate to be in an opened state, and 4) using a moisture curing hot-melt type adhesive containing, as a main component, an urethane polymer obtained by reacting a polyhydroxy compound with an excess amount of a polyisocyante compound as an adhesive for fixing the solar battery panel to the frame, there can be produced a solar battery module wherein the above problems have entirely been improved. The solar battery module and the process for producing the same was filed (Japanese Patent Application No. 6-155623).